Electrical alarm.



J. G. CLEMENS.

ELECTRICAL ALARM.

APPLICATION FILED JUNE 3,19l3.

L okra 6; (kIVLGILfiLEl/Itl! 3 @24 l 4 8 g W 8 m v I w Q, 9 I/ 8 #52,??? s V r: 5 \m x x J 1 Q & 4 n4 7 :3 I a i i JOHN G. CLEMENS, OF BUFFALO, NEW YORK.

ELECTRICAL ALARM.

Specification of Letters Patent.

Patented Dec. 5, 1916.

Application filed June 3, '1913. Serial No. 771,391.

To all whom it may concern:

Be it known that I, JOHN G. CLEMENS, a citizen of .the United States, residing at Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Electrical Alarms, of which the following is a specification.

My invention relates to electrical alarms such as are placed in action in response to alternating currents.

My invention has for its primary object the provision of an alarm which can be used in connection with alternating electric currents, such as furnished by electric companies for lighting and power purposes, the employment of which for actuating alarms embodying my invention eliminates the use of electric batteries which become exhausted from time to time and require constant attention.

My invention is particularly adapted for use in dwellings for signaling from entrance doors or from one portion of the house to another, and in connection with the same any suitable electrical appliance, such as a transformer, is introduced between the current feed line and the alarm for reducing the voltage, and as such appliance forms no part of my invention and will be apparent to those skilled in the art, I deem it unnecessary to illustrate or describe the same. It may, however, be here stated that electrical .alarms as now constructed cannot be successfully used in connectlon wlth alternating electrical currents, and for all practlcal purposes are energized with the usual batteries.

My invention also has for its object the provision of simple and efficacious means for adjusting the same so arranged that when once adjusted it will be maintained in adjusted position.

Itv further has for its object the employment of such adjusting means that the pitch or tone of the alarm will be changedso that a variation in sound can be had ranging from a loud and sharp alarm at high pitch to a mufiied low pitch alarm. This is very desirable, since it enables the use of one style and size of alarm for all purposes within a dwelling and by adjusting the. alarms of a battery employed so that each will have a different pitch or tone than the remaining alarms of the battery, the place from which the alarm is given can be easily determined.

With the above and other objects in view, my invention consists in a magnet energized by an electric alternating current and a member within the magnetic field of said magnet capable of vibrating and giving an alarm.

It also consists in a support, a magnet supported thereby, and a shell or other vibrat- 1ng element, said magnet and shell or other vibrating element being relatively movable.

It further consists in the construction, arrangement and combination of parts and in the relative adjustment of devices to be hereinafter described and particularly pointed out in the subjoined claims.

In the drawings,Figure 1 is a central longitudinal section of one embodiment of my invention. Fig. 2 is a transverse section taken on line 2-2, Fig. 1. Fig. 3 is a detached perspective view of the support. Fig. 1 is a central longitudinal section of another embodiment or modification of my invention. Fig. 5 is a side elevation of my invention equipped with-a bell and hammer.

Referring now to the drawings in detail, similar numerals of reference refer to similar parts in the several figures.

The reference numeral 6 designates a support adapted to be secured to a wall or other suitable object, and is adapted to carry the remaining parts of the alarm. In preferred form, this support comprises a cross bar 7 having at opposite ends segmental wings 8 which stand atright angles thereto.

Frictionally fitting over the segmental wings 8, is a cylindrical shell or cup 9, which is by preference made in two parts, one part 10 comprising the cylindrical wall of the shell or cup having at its outer end an inwardly-tapering flange 11 and the other part being a disk 12 of magnetic material which is removably held within part 10 and serves as the outer end wall or head of said shell or cup. The part 10 has an internal annular groove 13 at the point where the cylindrical wall joins the tapering flange 11, and as this flange is arranged at an obtuse angle to" said cylindrical wall, the outer angle only, formed by the edge and outer face of the disk 12, bears against the flange 11 at a point in close proximity to said annular groove. This results in a slight space being formed betweenthe outer or marginal por: tion of said flange and said disk, thus allow ing said disk every freedom to vibrate, as will appear hereinafter. The disk 12 is retained in position by a divided circular spring 15 which is inserted 1n the shell or cup and is sprung into the annular groove 13 therein, said spring bearin only against the inner angle of the disk ormed by the.

edge and inner face of the same. The shell or cup is retained on the support 6 by frictional engagement therewith and is ad ustable on said support in the direction of its axis, so that the outer end wall or head 12 may be adjusted toward or from said suport. p The shell or cup and the support may be constructed of sheet metal, thus enabling their being cheaply produced, and although I'have described the shell as constructed in two parts, it may be otherwise formed.

Projecting centrally from the support and co-axial with the shell is an electro-magnet 16 having a central threaded bore 17 to enable its being threaded onto a supportlng screw 18 passed through the support 6, said screw being retained in said support by means of a nut 19 which bears against the support. By this means the electro-magnet may be adjusted toward and from the support and be maintained in adjusted position by a nut 20 on said supporting screw adapted to bear against the inner end of said magnet. It is apparent therefore, that the electro-magnet is adjustable on the support, so as to bring the outer end thereof the desired distance fro imsaid support, and also that the shell or cup is adjustable on said support which enables the outer end wall or head thereof to be adjusted relative to' said electromagnet.

When adjusting the shell or cup relative to the electro-magnet, the space between the end Wall or head of said shell or cup and the outer end of the core of the magnet may be increased or diminished, and this variation in space, which is fully within the magnetic field, causes the variation in pitch or tone of the alarm, caused by energizing the magnet, the alternating current employed for this purpose acting through the medium of said magnet to vibrate the end wall or head of said shell or cup, and the varied distances between said end wall or head and'said magnet, control the extent of vibration of said wall or head, the current or magnetic flux being more powerful at a certain distance than at closer or farther range, and this results in the difference in pitch or tone, ranging from a mufiied low sound to a sharp high sound, the sound being caused by the rapping of the disk against the core when vibrating. Any desired tonation and degree of sound within the range of the shell or cup can be easily obtained by adjusting the latter on its support, thus enabling the use of one size shell or cup for alarms sounded termine the point from which the alarm is given; it being of course understood that the electro-magnet has its terminals electrically connected, as is common, and that the alarm is given by actuation of a push button, switch, or the like included in the circuit to which the magnet is connected. When, however, it is found that the difference in tone, or pitch within the range of the alarm is insufiicient for the purpose intended, the sup: port 6 may be used in connection with a shallower or a deeper shell or cup and the electro-magnet adjusted on its support accordingly. The difference inthe depth of the shell or cup will considerably change the .pitch or tone caused by the vibration of the end wall or head thereof, and in such cases, the shell or cup is made of the same diameter so that it will also be frictionally retained on the support 6 and be adjustable thereon. By frictionally supporting the shell or cup on the support 6, all screw or other fastening device, which easily become loose and lost, are entirely dispensed with.

In the modification shown inFig. 4, the

shell, designated 21 is rigidly supported on a support 22, the shell in this instance being drum-like in formation and comprising a cylindrical central or body portion 23, and two heads 24. The central or body portion 28 is made of insulating material and has perforations 25 therein to allow the escape of sound. The heads 24 have flanges 26 which surround the ends of the central or body portion and each of theseflanges has slots 27 extending in the direction "of the axis ofthe shell through which are passed screws 28 that take into the body portion. In this manner the heads may be adjusted on the body portion with reference to an electro-magnet 29 in the shell, said magnet being secured within a frame 30 secured in said shell in any approved manner. When the heads are secured in the desired adjusted position, thefianges thereof are rigid with the body-portion of the shell, the effect being similar to a devicein which the body portion and 'head are formed integrally. The core of the magnet may have its end adjacent the vibrating head provided with a depression 31, which serves to create a shrill or higher pitched sound than otherwise; this depression, however, is not necessary to the operation of the alarm, and is desirable only where the sound must carry mer head 33 at one end of a lever 34 which is pivoted between its ends andhas its other end in contact with the vibrating head of the shell or cup 9, the vibrations of which are imparted to the hammer head and the bell thereby actuated.

Having thus described my invention, what I claim is,-

1. An alarm of the kind described, comprising an electro-magnet having a solid core and a depression in one end of its core and a shell of magnetic material in which said magnet is confined, said shell having one wall thereof within the magnetic field of said magnet.

2. An alarm of the kind described, comprising a support, an electro-magnet carried by said support and an inclosure for said electro-magnet frictionally adjustable on said support, said inclosure having a wall capable of vibrating under the influence of an alternating current energizing said magnet and being moved toward and from one end of said magnet when adjusting said inclosure on said support.

3. An alarm of the kind described, comprising a support having segmental wings, a cylindrical shell. of magnetic material having its peripheral wall frictionally engaging said wings, and an electro-magnet carried by said support and arranged centrally within said shell in operative relation to one wall thereof.

4. An alarm of the kind described, comprising a support having a cross bar and segmental wings at opposite ends of said cross bar standing at right angles thereto, a cylindrical shell open at one end fitting frictionally onto said wings, and an electro-magnet carried by said support and arranged axially within said shell and in electrically spaced relation to the end wall thereof, said end wall being of magnetic material.

5. An alarm of the kind described, comprising an electro-magnet, a shell placed over said magnet and having a cylindrical body portion provided with a tapering flange at its outer end, and a disk fitting into said shell and bearing against said flange with its edge, said disk being arranged to vibrate when said magnet is energized and said shell being frictionally adjustable oi'ersaid magnet.

6. An alarm of the kind described, comprising a shell having a cylindrical body portion with an internal annular groove at its outer end and a tapering flange arranged at an obtuse angle to the cylindrical wall of said shell, a disk fitting into said shell and having its marginal portion bearing against said flange with the marginal portion of the latter spaced therefrom, a divided annular springfitted into said groove and locking said disk in position, and an electro-magnet arranged axially in said shell in operative relation to said disk, said shell being frictionally adjustable over said magnet.

In testimony whereof I .have affixed my signature in presence of two witnesses.

JOHN G. CLEMENS.

Witnesses EMIL NEUHART, JACOB OBERST, Jr. 

